Category Archives: drought

A Dry and Dusty Start to the Los Angeles Rain Year

dry and dusty Upper Las Virgenes Canyon Open Space Preserve (Ahmanson Ranch)

Except for a teaser storm system in early November that brought a smattering of rain to the metro area and some snow to the mountains, the Los Angeles rain year is off to a parched start.

As of December 1, Downtown Los Angeles (USC) has recorded only 0.11 inch of rain since July 1. Along with 1995, this is the 7th driest start to the rain year over the 144 years weather records have been kept in L.A.

Update December 29, 2020. In the first significant storm of the rain year, Downtown Los Angeles recorded 1.82 inch of rain, bringing the rainfall total up to 1.95 inches. The storm total was more than generally forecast, but L.A. is still about 2 inches below normal for the date. The rain does move 2020 out of contention for the driest first six months of the rain year.

Update December 20, 2020. The period July 1 – December 20, 2020 is the driest on record (for that date range) for Los Angeles. As of December 20, the rainfall total for Downtown Los Angeles (USC) remains at 0.11 inch.

While “past performance may not be indicative of future results,” I was curious to see if, historically, a dry start to the rain year has generally resulted in below average annual rainfall.

There have been 16 years in which Los Angeles precipitation was 0.25 inch or less for the period July 1 to December 1. Rain year precipitation (July 1 – June 30) for those years varied from a low of 4.79 inches in 2017, to a high of 23.43 inches in 1937. Overall, these years averaged 11.34 inches of rain annually, which is 3.66 inches below the current normal of 14.93 inches.

Whether or not annual rainfall this rain year is below normal we’ll have to see. An important consideration is that La Nina conditions are present in the equatorial Pacific. This doesn’t necessarily mean less rainfall in the Los Angeles area, but taking into account a number of factors, the Climate Prediction Center is projecting below average precipitation this Winter in Southern California.

The title photo of silhouetted mountain bikers is from this afternoon’s run at Upper Las Virgenes Canyon Open Space Preserve (Ahmanson Ranch). The image is an example of a “silhouette illusion.” Are the riders going toward or away from the camera?

Back to the Stone Canyon Trail

Top of the Stone Canyon Trail on Mt. Lukens
Top of the Stone Canyon Trail and the summit of Mt. Lukens.

At the deepest part of the creek, the cold water reached mid-thigh. I’d futzed around looking for a way to rock hop across Big Tujunga Creek, but didn’t find one.

With squishy shoes, I followed the trail eastward along the creek. A little past Stone Canyon wash, the trail turned toward Mt. Lukens and started to climb.

Chaparral whitethorn along the Stone Canyon Trail
Chaparral whitethorn

The Stone Canyon Trail is one of the trails on my list of trails less-traveled. Today, the trail choice had been between the Stone Canyon Trail and Condor Peak Trail. Recalling the difficulty of the Condor Peak Trail, I thought it would be better to do Mt. Lukens first, and save Condor Peak for later.

As I worked up the trail, I marveled at its condition. It was in surprisingly good shape! It had been groomed relatively recently, and I mentally thanked the person or group that had taken care of the trail. With a clear trail and cool morning temperature, it felt good to push the pace up the steep trail.

Stone Canyon from the Stone Canyon Trail
Stone Canyon

The last time I’d done this route was in November 2016. That outing followed five years of drought. With growth suppressed, the upper half of the trail was only moderately overgrown, and I did not see any poison oak. Ever the optimist, I thought today’s conditions might be even better.

Remnants of scrub oak burned in the 2009 Station Fire
Remnants of scrub oak burned in the 2009 Station Fire

Not this time. I don’t know if Winter rains or the pandemic had intervened, but about halfway up the peak, the trailwork abruptly ended. The upper half of the trail was badly overgrown, and at inconvenient times Spring-green poison oak lined the trail. In a few places, fallen scrub oak trees — burned in the Station Fire — were mixed in with the brush. Where the 2016 ascent had been after a drought, today’s followed a wet period in which three out of the past four years have had normal or above-normal rainfall.

Prickly phlox along the Stone Canyon Trail
Prickly phlox

With care, patience, and a bit of bushwhacking, I eventually reached the top of the Stone Canyon Trail and the old dirt road on the west side of the peak. A few minutes later I stood alone on the summit of Mt. Lukens. I had not seen anyone on the ascent and would not encounter anyone on the way down.

Here’s a 3D Cesium interactive view that shows a GPS track of the route up and down the Stone Canyon Trail on Mt. Lukens. The view can be zoomed, tilted, rotated, and panned. Placemark and track locations are approximate and subject to errors.

Related post: Mt. Lukens, Then and Now

Upper Las Virgenes Creek Still Flowing in Mid-July

Upper Las Virgenes Creek, July 17, 2019.

Following our five year drought, Downtown Los Angeles and many neighboring areas recorded above-average rainfall in two of the last three rain years. This has had obvious and observable effects on the area’s plants and animals and aided in the ongoing recovery of habitats affected by drought and wildfire.

This is the first time since the Summer of 2011 that there has been flowing water in upper Las Virgenes Creek in mid-July at the crossing near the Cheeseboro connector. It’s just a trickle, but keep in mind that during some of the drought years, this section of upper Las Virgenes Creek never flowed.

Update November 19, 2019. Increased surface water and pooling in Upper Las Virgenes Creek. See the post Running Into Fall.

Update August 28, 2019.  The surface flow of Upper Las Virgenes Creek near the Cheeseboro connector is down to a bare trickle and some small pools.

Update August 7, 2019. Upper Las Virgenes Creek is still trickling.

Notes: In rain year 2016-17 Downtown Los Angeles (USC) recorded 19.00 inches of rain from July 1 to June 30, and in 2018-19, 18.82 inches. During the intervening rain year, 2017-18, only 4.79 inches was recorded.

Lasky Mesa: Dark Clouds and Sun

Dark Clouds and Sun. Photography by Gary Valle'.

From a run this May in Upper Las Virgenes Canyon Open Space Preserve (Ahmanson Ranch).

Normal rainfall for May at Downtown Los Angeles (USC) is 0.26 inch. This year Los Angeles recorded 0.81 inch in May, according to the NWS .

It was definitely wet and cool! Nineteen days were partly cloudy to cloudy. Ten days recorded at least a trace of rain. The average high was 70 degrees.

Oddly, during our recent drought, above normal May rainfall totals were recorded in 2011 (0.45 inch), 2013 (0.71 inch), and 2015 (0.93 inch). The most rainfall recorded in May at Los Angeles was 3.57 inches in 1921.

After the Woolsey Fire: Malibu Creek State Park Redwoods, M*A*S*H Site and Bulldog Climb

I’d done a long run the day before in Pt. Mugu State Park, so the plan for this morning was to do a short run and check out the Woolsey Fire impacts between Century Lake and the M*A*S*H site in Malibu Creek State Park.

In addition to checking the condition of the coast live oaks and other native trees, I was curious to see how the coast redwoods along the Forest Trail had fared. These trees were planted nearly a century ago and in recent years have struggled with the drought. Had they survived the fire?

It had been about a year since I had checked on the redwoods. The good news is that a few of them still appear to be viable. The bottom limbs on some of the trees were scorched, but I think they will be OK. Of the 16 or so redwoods, about five have died, about five are in poor shape, and five or six appear to be OK. There is one young naturally occurring tree that was severely scorched and may not survive. We’ll just have to see.

While there was some damage to the M*A*S*H site, the picnic tables, ambulance, and signpost made it through the fire. Some repairs will be necessary.

I was supposed to turn around at the M*A*S*H site, but you know how that goes. I wanted to see “just a little” of the Bulldog climb… and a little more… and a little more. I finally ran out of time about 2.5 miles up Bulldog Mtwy and headed back.

Even when you expect it, it is sobering to see areas of high soil burn severity. Thirty-six years of robust chaparral growth were just… gone. Also startling were the stream flows and debris flows that resulted from “only” about 1.5 – 2.0 inches of rainfall in early December. An atmospheric river event of the magnitude that caused the Malibu Creek flooding in February 2017 would be catastrophic.

A lot of work had been done on Bulldog Mtwy. It had been repaired and graded. Where there was still brush and trees along the road the branches had been trimmed!

Here are a few photos taken along the way.

Some related posts: Malibu Creek Flooding, Malibu Creek State Park Redwoods: Fighting the Drought

Finally — a Few Wildflowers!

Bush sunflower

As of March 1, Downtown Los Angeles had recorded only 1.99 inches rain over the past eight months. Most of that was recorded in one storm in early January. It was the second driest July 1 – February 28 on record.

Following the January storm, temperatures warmed up and stayed relatively warm for much of the next 30 days. In the West San Fernando Valley the high temperature hit 89 °F at Pierce College on February 4, and was over 80 °F for 12 consecutive days. Some plants (and some rattlesnakes) responded as if it was Spring.

In mid February Winter returned, with cool daytime temperatures and cold nights. There were Frost and Freeze Warnings on several nights.

In March the ridiculously resilient ridge of high pressure over the West Coast finally relented, resulting in above normal rainfall. It took awhile, but the March rain and April sun eventually produced an assortment of wildflowers.

Here are some wildflower photos from recent runs at Ahmanson Ranch, Malibu Creek State Park and Topanga State Park.